As an apparatus capable of easily understanding a program display, one conventional apparatus is disclosed in Japanese Laid-open Utility Model Application No. Hei-6-33207. Referring now to FIG. 7 and FIG. 8, this conventional apparatus will be explained. FIG. 8 is a structural diagram of the conventional apparatus. Reference numeral 61 shows a central control apparatus (CPU) for controlling this apparatus in a unified manner; reference numeral 62 shows a control program memory (ROM) for storing thereinto a control program which executes a list-form display processing operation of program numbers of an NC program; and reference numeral 63 indicates a RAM for storing thereinto the data based upon sorts of the files, such as data under execution, or multiplicity data indicating frequencies of use of the programs to be displayed in a list form, and so on. Also, reference numeral 64 represents a keyboard which is used to select a desirable program from a main program by the keyboard operation; reference numeral 65 indicates a display apparatus (CRT) for displaying the list-form display data of the program numbers; reference numeral 66 shows an NC program memory for storing thereinto an NC program; and reference numeral 67 indicates a program number list-form display processing unit for performing the list-form display process operation of the program numbers of the NC program.
When the list-form display data of the NC program numbers, and the like are outputted on the CRT 65, the CRT screen display is made as shown in FIG. 7. That is to say, when an operator designates a certain program number of a predetermined NC program, the CPU 61 reads the predetermined NC program (namely, main program) from the program memory 66, and sequentially stores only the numbers of such programs linked to the main program into the RAM 63. The CPU 61 displays the numbers of the stored programs as a sequential list on an area PL of “program number list” on the CRT screen, and displays the numbers of the stored programs on an area CL of “call list” in such a case that program numbers as to a family relationship of a desirable program. It should be noted that symbol “K” indicates a cursor. The cursor K displayed by the frame indicated by a two-dot chain line is set to the number of the desirable program, so that the number of the program within the cursor K is designated.
Next, a flow operation of the program number list-form display processing unit 67 is explained. It is so assumed that while a desirable main program has been previously designated by the operator, a number list of programs linked to the main program is displayed on the area PL of “program number list” on the CRT screen. The operator selects a desirable program number so as to initiate the program list-form display process operation.
The CPU 61 executes a reading process operation in such a manner that the selected program number is read every 1 block, or several blocks. The CPU 61 determines as to whether or not the read block corresponds to a sub-program calling instruction. When a program number is read, since multiplicity data is added thereto, the CPU 61 can discriminate a family relationship among programs.
In the apparatus disclosed in the prior art, while the operator recognizes which main program is selected, the operator must designate the program number thereof. As a consequence, in general, there are many cases such that a main program can be discriminated from a sub-program based upon digits of numbers. To conduct such a program management, some sort of the rules for a program numbering way must be produced by all of the operators. As a consequence, in the case such that a digit of a program number is erroneously entered, a main program cannot be found out. Also, with respect to work programs for operating industrial robots, due to a technical revolution of the semiconductor memory technologies, huge numbers of programs comes to be registered, so that so much cumbersome operations are required for locating a main program from a program list.
Also, since programs are sequentially analyzed when a main program is designated, in the case such that programs are large, lengthy time might be required. In other words, the following problem would occur. That is, since a family relationship of programs cannot be immediately discriminated after a main program initiation signal is entered, such an apparatus which is disclosed only in the list-form display cannot be applied.